Tamika is one of the most-described characters in Night Vale -- stocky build, dark eyes, currently age 14 (and, so far, aging at a normal rate), and while her race isn't stated outright, the name and voice actress make TPTB's intentions pretty clear.

As for personal fanon: I always draw her with her hair in twists, because you need something you can pull up and out of the way easily if you're going into combat. At this point it's probably a fair bet she has some scars.